Anatomically conformable foam support pad

ABSTRACT

A convoluted foam pad for supporting a reclining human body on a bed including an area for supporting the shoulders of a body, an area for supporting the tail portion of a body and a general support area surrounding the shoulder and tail support areas for supporting the remainder of the body. Each support area is formed by peaks arranged in rows, wherein each peak has a flat top and is spaced from any adjacent peak in the same row by a valley. The average valley thickness of the valleys in both the shoulder support area and the tail support area are less than the average valley thickness of the valleys in the general support area. Another aspect of the invention is a method of manufacturing convoluted foam pads including compressing a foam block between two rollers having radially extended fingers of varying effective heights, cutting the compressed block into halves having varying peak heights and valleys having varying valley floor heights, and cutting the tops of the peaks off the create areas having lower volumes of foam than other areas.

BACKGROUND OF THE INVENTION

This invention relates to pads for supporting the seated and recumbenthuman body which redistribute body weight away from bony prominentareas, which areas are the most susceptible to the formation of pressureulcers and, in particular, to convoluted foam pads used for thispurpose.

Two of the primary causes of pressure ulcers are pressure and moisture.The pressure results from the supporting surface resisting the force ofgravity on the body. For mattresses, this pressure is typically thehighest beneath the shoulder (the scapulae) and tail (the sacrum andtrochanter), generally the areas of greatest mass and projection. Inthese high pressure areas, the pressure against the body can besufficient to occlude the capillaries and lymph vessels, therebypreventing the circulation of oxygen and nutrients to the skin. Inaddition, because airflow over these skin areas is typically preventeddue to the surface of the mattress, greater amounts of moisture areexcreted for the dissipation of heat and waste. Over a sufficient periodof time, the combination of high pressure and moisture will lead to theformation of pressure ulcers.

In an effort to combat the formation of pressure ulcers among patients,hospitals utilize a number of types of bed pads for their patients whofall into high risk categories. These products include static air, waterand foam support pads. Although these pads cannot reduce the overallresistance of the mattress to the weight of the body, they can reducethe level of pressure on the areas of highest pressure by redistributingthe load and allowing a greater portion of the pad to support the body.Each of these types of pads has different advantages and disadvantages.

Generally, static air and water support pads provide superior highpressure reduction capabilities at the bony prominences, but permit onlylimited air flow and heat dissipation. In addition, both static air andwater support pads require filling, are susceptible to leaks and tend to"bottom out" (i.e., permit the weight of the user to displace the air orwater in the pad to the extent that the user is supported by themattress, rather than by the air or water cushion). Static water supportpads also are undesirable in that they are heavy and unwieldy totransport. While pumps and valves can be used to vary the pressureresistance of the static air and water pads over time, these featuresrender the pad both expensive and difficult to install and transport.

Convoluted foam pads, on the other hand, are generally relativelyinexpensive and easily transported, while providing superior air flowpotential and moisture reduction capabilities. Unfortunately, despiteconsiderable study and effort, it has proved exceedingly difficult todevelop an easily manufactured convoluted foam pad which is capable ofproviding pressure reduction characteristics comparable to static airand water support pads.

The manufacture of convoluted foam pads continues to largely follow themethods taught by U.S. Pat. No. 3,431,802, which patent is herebyincorporated by reference. The pads are typically formed by feeding afoam block between two cooperating parallel cylinders, each of which hasa undulated surface. The cylinders rotate towards one another and arespaced so that the block inserted between them is compressed between thecylinders and is driven against a cutting edge which slices the block inhalf. Each half generally comprises alternating rows of peaks andvalleys, in checkerboard fashion. The resulting halves are perfectlymatched so that when one half is laid upon the other, the tops of thepeaks of one half rest against the floor of the valleys of the otherhalf forming a solid block. In addition, although it is possible tomanufacture pads which are not the mirror image or reflection of oneanother, this is rarely done, as it would typically result in only oneusable half, thereby significantly increasing material costs.

One convoluted foam pad currently in use is disclosed in U.S. Pat. No.4,686,724. The pad is comprises alternating columns of peaks and valleysin checkerboard fashion. Air channels are stamped, press cut or lasercut through the floor of the valleys to the bottom face of the pad,leaving removable plugs used to selectively control the amount ofaeration and dissipation of body heat permitted by the pad.

In one embodiment, the peaks of the pad are "topped off" to create abroken flat surface, interposed with valleys, with the distance betweenthe floor of each valley and the bottom surface of the pad beingconstant. Within each valley is a channel extending from the valleyfloor to the flat bottom face of the pad. The patent teaches that a skinarea of 1.25 inches in diameter or less, even though denied aircirculation, can sustain itself from air circulating in an adjacentarea. Therefore, by limiting each peak top to a diameter of 1.25 inchesor less, the occurrence of decubitus ulcers can, according to thepatent, be virtually eliminated. Unfortunately, the use of this uniformpad with its removable plugs has found little acceptance in practice,perhaps because the removal and replacement of the individual plugs isrelatively difficult and time consuming.

A second convoluted foam pad is disclosed in U.S. Pat. No. 4,620,337.The pad is designed to prevent the formation of decubitus ulcers byminimizing the amount of pressure exerted on the body. The pad has threedistinct sections: a convoluted head supporting section; a ribbed torsosupporting section; and a convoluted foot and leg supporting section. Aswith most foam pads which are manufactured from a block of uniformthickness, the sum of the distance from the bottom face of the pad tothe top of any peak (the "peak height") and the distance from the bottomface of the pad to the floor of any valley (the "base height" or "valleyfloor height") remains constant. This arises from the fact that althoughthe height of the undulating surface of the paired cylinders variesalong their length, the opposing undulating surfaces are of an equalheight.

The pad is designed on the premise that heavier portions of the body areless likely to develop pressure ulcers when they are supported by aportion of the pad with a lower peak to base ratio, and that lighterportions of the body are less likely to develop pressure ulcers whenthey are supported by a portion of the pad with a higher peak to baseratio. Accordingly, the ribs of the torso supporting section are shorterthan the average height of the peaks of the head or leg supportingsections, and the floors of the valleys of the torso supporting sectionare higher than the average height of the floors of the valleys of thehead or leg supporting sections. Unfortunately, however, the pressurereduction capabilities of this pad are significantly lower than thepressure reduction capabilities of static air or water support pads.

What is needed, therefore, is a convoluted foam pad which is easy tomanufacture and provides high pressure area reduction capabilitiescomparable to the static air and water support pads.

SUMMARY OF THE INVENTION

The present invention solves these problems by providing an easilymanufactured convoluted foam pad having pressure redistributioncapabilities comparable to the static air and water support pads and amethod of manufacturing the same.

One embodiment of the invention is a convoluted foam pad for supportingat least part of a human body having a solid flat lower face and a flatupper surface wherein at least one area of the pad provides lessresistance to the weight of the body than other areas of the pad.Desirably, the area providing this decreased resistance corresponds to aprotruding portion of the body, thereby allowing the body to sinkfarther into the pad.

Another embodiment of the invention is an elongate convoluted foam padfor supporting a reclining human body on a bed. The pad includes an areafor supporting the shoulders of a body, an area for supporting the tailportion of the body and a general support area surrounding the shoulderand tail support areas for supporting the remainder of the body. Eachsupport area is formed by flat-topped peaks arranged in rows, whereineach peak in the same row is spaced from any adjacent peak by a valley.

To decrease the average pressure levels on the shoulder and tailportions of the body, the average valley thickness (i.e., the averagevertical distance between the valley floors and the bottom of theportion of the pad directly beneath the respective valley floors) of thevalleys in both the shoulder support area and the tail support area areless than the average valley thickness of the valleys in the generalsupport area. This diminished valley thickness has the dual effect ofreducing the resistance of the pad to the weight of the tail andshoulder portions of the body and permitting the tail and shoulder areasof the body to sink farther into the pad. The increased deformation ofthe pad is significant in that, as the tail and shoulders of the bodysink further into the pad, the middle back and extremities exert greaterpressure against the general support area of the pad. In addition, thefarther the tail and shoulder portions of the body sink into the pad,the greater the amount of total surface area of the pad in contact withthe tail and shoulders portions of the body, resulting in a decrease inthe average amount of resistance pressure exerted by the pad per squareinch in these critical areas.

Desirably, the pad has a flat upper face formed by the flat tops of thepeaks of the pad which all lie substantially in a single plane and asolid flat lower face, without holes or cavities. The pad is desirablymade from an open cell expanded plastic polyurethane foam with a densityof between one and three pounds per cubic foot, and has a peak thicknessof between one and five inches.

Another aspect of the invention is a method of manufacturing convolutedfoam pads. The method includes compressing a foam block between tworollers having radially extended fingers of varying effective heights.The compressed block is then cut into two halves to form peaks andvalleys. As a result of the varying effective heights of the fingers ofthe rollers, the peaks will have varying peak heights and the valleyswill have varying valley floor heights. The tops of the peaks are thencut off to create areas having lower volumes of foam than other areas.These low foam volume areas will tend to provide less resistance topressure than the areas of the pad having a higher volume of foam.

Desirably, the tops of the peaks are cut so the top of each peak will bein substantially the same plane. Where some of the corners of the peaksare connected by webbing, the method may also include the separatingsome of the peaks connected by webbing to decrease the resistance of thelocale including the separated peaks to pressure.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features of the invention will now be described withreference to drawings for preferred embodiment is intended toillustrate, and not to limit, the invention, and in which:

FIG. 1 view is a perspective view illustrating a foam block beinginserted between a pair of cylindrical rollers;

FIG. 2 is an enlarged partial perspective view illustrating the fingersof the rollers of FIG. 1;

FIG. 3 is an enlarged exploded perspective view of one of the fingers ofFIG. 2;

FIG. 4 is an illustration of two convoluted halves of a block afterinsertion into the apparatus of FIG. 1;

FIG. 5 illustrates the fit between the halves of the block of FIG. 4;

FIG. 6 illustrates the topping-off of the peaks of one of the halves ofFIG. 4;

FIG. 7 illustrates the half of FIG. 6 after being saw cut;

FIG. 8 illustrates the clip cutting of the half of FIG. 7;

FIG. 9 is a schematic plan view illustrating the general spacing of thetail and shoulder regions of a bed pad made in accordance with theprinciples of the present invention;

FIG. 10 is a schematic plan view of a pillow made in accordance with theprinciples of the present invention illustrating the shape of the headand neck support area in phantom;

FIG. 11 is a schematic plan view of a wheelchair pad made in accordancewith the principles of the present invention illustrating the shape ofthe buttock and thigh support area in phantom;

FIG. 12 is a perspective view of the pillow of FIG. 10;

FIG. 13 is a perspective view of the wheelchair pad of FIG. 11;

FIG. 14 is a perspective view of the bed of FIG. 9; and

FIG. 15 is a sectional view taken along line 15-15 of FIG. 14illustrating the varying valley thicknesses of the different areas ofthe bed pad.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

FIG. 1 shows an apparatus 11 for manufacturing convoluted foam pads. Theapparatus 11 includes a pair of cooperating parallel rollers, 13 and 14,each of which has a cylindrical body and an undulated surface. As moreclearly shown in FIG. 2, the undulated surface of each roller is formedby a plurality of fingers 15 of generally rectangular cross sectionextending radially from its cylindrical body. Naturally, if desired,another shape of finger could be utilized. The fingers 15 are arrangedin vertical and horizontal rows. Fingers in vertically adjacent rows arestaggered vertically a circumferential distance approximately equal tothe vertical width of the fingers. Fingers in horizontally adjacent rowsare staggered horizontally a circumferential distance approximatelyequal to the horizontal width of the fingers.

The rotating rollers, 13 and 14, compress and drive the foam block 19against a cutter (a guard 17 for which is shown in FIG. 4). As shown inFIG. 1, the upper roller rotates counterclockwise and the lower rotatesclockwise. This rotation is synchronized so the fingers 15 of therespective rollers are opposed by the spaces 21 between the fingers ofthe opposite roller, rather than directly by its fingers 15. Inaddition, to obtain pads which are virtually a mirror image of oneanother, all fingers 15 on a given side of, and vertically adjacent to,the spaces of one roller have an effective height equal to the effectiveheight of the finger of the opposing roller which opposes the space.

As best seen in FIGS. 2 and 3, the radial height of each of the fingers15 is equal. Selected fingers, however, have a greater effective radialheight as a result of one or more flat rectangular caps 23 or platesbeing secured to the radial outer end of the finger by a bolt 25threadably secured within a tapped bore 27 extending radially throughthe center of the finger. Naturally, the thickness of the caps 23 can bevaried depending upon the given application. A countersink 29 may beprovided around the bore 27 of the outer cap, so that the head of thebolt 25 is flush with the outer face 31 of the cap.

Referring to FIG. 4, after the foam block 19 is compressed between therollers, it is driven against the cutter (not shown) which slices theblock 19 into halves 33. As shown in FIG. 5, the resulting halves 33 arevirtually a perfect mirror image of one another, with each peak 35 ofone half corresponding to an adjacent peak 37 of equal size on the otherhalf. On the other hand, the variance in the effective height of thefingers 15 results both in peaks with varying peak heights P, andvalleys with varying valley floor heights V. Because the pad is cut froma single block 19, however, the sum of the valley floor height and thecorresponding peak height will equal a constant, so long as the blockbeing cut is of uniform thickness.

By varying the effective height of the fingers less than one quarter ofan inch, the heights of the peaks 42 of the resulting foam halves 33 canbe varied 3-4 inches. Naturally, since the block halves 33 are a mirrorimage of one another, the base height of the corresponding valleys 44will vary an equal amount. Thus, although the peak to base ratio of thepad can be made to vary widely, essentially the same volume of foam ispresent to resist the weight of a given area of the body supported bythe pad.

As shown in FIG. 6, the tops 39 of the peaks 42 are then removed with aband saw 41 or other suitable cutting device, thereby leaving arectangular pad 43 with a flat solid lower face 45 and a substantiallyflat upper face 47 comprised of the flat tops 49 of the peaks 42. Asshown in FIG. 7, the pad 43 comprises adjacent rows of peaks 42 ofgenerally rectangular cross section, each of which are separated byvalleys 44, also of generally rectangular cross section. Since the peaks42 in adjacent rows are staggered, the overall effect is a checkerboardpattern, with the corners of the peaks 42 in adjacent rows connected bywebbing 51 extending between the peaks 42 to the floor of the valleys44. The webbing 51 between some peaks 42 will extend from the top of thepeak downward to the floor of the valley between them. Between otherpeaks 42, especially those with lower valley heights, the webbing 51will be spaced below the tops of the peaks 42 and extend downward to thefloor of the valley between them. For example, referring to FIG. 7, apeak 57, in a row of peaks 59 between a second and third row of peaks,61 and 63, respectively, has a first corner 65 connected by webbing 51to a corner of a first peak 67 in the second row 61 and a second corner69 which is connected by webbing 51 to a corner of a second peak 71 inthe second row 61. Likewise, the peak 57 has a third corner 73 which isconnected by webbing 51 to a corner of a first peak 75 in the third row63 and a fourth corner 77 which is connected by webbing 51 to a secondpeak 79 in the third row 63.

To obtain two generally uniform pads from a single block 19 it isdesirable that the tops of the peaks 42 are cut off at a point midwaybetween the tops of the peaks 42 and the floor of the valleys 44.Although each of the remaining flat-topped peaks 42 will have a uniformpeak height, the base height of the valley floors varies in proportionto the effective height of the finger which created it. Since the pad 43has a flat lower face 45, the peak height of each peak is equal to itspeak thickness (i.e., the vertical distance between the top of the peakand the bottom of the portion of the pad 43 directly beneath the peak).Naturally, if the lower face of the pad 43 included an opening beneaththe peak, this would not be the case. Likewise, the valley floor heightof each valley of the illustrated pad 43 is equal to its valleythickness (i.e., the vertical distance between the valley floor and thebottom of the portion of the pad 43 directly beneath the valley floor).If the lower face 45 of the pad 43 included an opening beneath thevalley floor, however, this would not be the case.

By increasing the effective height of the fingers 15 which correspond tothe areas of the pad 43 supporting the shoulder and tail portions of thebody, taller peaks 42 and lower valleys 44 are formed in those areas ofthe pad 43. By evening out the heights of the peaks 42 by topping themoff at a certain height, one is left with a smaller volume of foam toresist the weight of the that portion of the body. It has been foundthat the smaller the volume of foam in a given area, the smaller thelevel of resistance of the foam to the weight of the body will be. Bydecreasing the volume of foam beneath these heavier portions of thebody, the more the weight of the body portions to overcome theresistance of the pad and sink into the foam. This, in turn, increasesthe surface area of the pad in contact with the body portion, therebyfurther diminishing the level of pressure exerted on the skin of thebody per unit area. In addition, since both the shoulder and tailportion of the body protrude farther than the lighter portions, as theshoulder and tail portions sink into the pad, the pressure of the pad onthe less protruding portions (e.g., the middle of the back) willincrease, thereby relieving pressure from the tail and shoulder portionsof the body.

The pad of the present invention can be made from a wide variety oftypes of foam of varying density and thickness. It has been found,however, that the desired combination of cushioning and support isobtained from an open cell expanded plastic polyurethane foam with adensity of between one and three pounds per cubic foot, preferably 1.5pounds. The peak and valley thickness of the pad 43 is desirablysufficient to ensure that the body supported by the pad does not bottomout. For a bed pad 43 having a density of between 1-3 pounds, a peakthickness of between 3-5 inches, and a valley thickness of approximatelyone half of an inch has been found to be sufficient to prevent bottomingout in most instances. In home health care applications, however,significant benefits can be realized from a pad with a peak thickness aslow as one inch and a valley thickness as low as one-eighth of an inch,which imposes a concavity to the bed surface for comfort, as opposed totherapeutic purposes.

At times, in addition to the standardized pressure reductioncapabilities of the pad 43, it is desirable in the case of burns orother localized injury to decrease the level of pressure resistance in agiven area of the pad. As illustrated in FIG. 8 this may be accomplishedby cutting the webbing 51 connecting the corners of the peaks 42 inadjacent rows to separate the peaks 42. This has the effect ofdecreasing the "hammock effect" between the separated peaks. The hammockeffect results from neighboring peaks resisting the tendency of aconnected peak to be compressed below their level, much like two treesresist the tendency of a hammock to sag to the ground in response to theweight on the hammock. The cutting of the webbing 51 largely eliminatesthis effect, thereby decreasing the capacity of the locale whichincludes the separated peak to resist the weight of a body.

Referring to FIG. 9, there is shown a schematic view of a bed pad 43manufactured in accordance with the principles of the present invention.As further shown in FIGS. 14, the bed pad 43 will generally have anoverall length of between 60-90 inches and a width of between 25-40inches, depending upon the length and width of the mattress beingcovered. The illustrated pad 43 has a length of approximately 72 inchesand a width of approximately 35 inches. The shoulder support area 81 andtail support area 83 of the pad 43 are positioned to correspond to thenormal position of the shoulder and tail portions of the body of theintended user and are surrounded by the general support area 84 of thepad 43. The shoulder support area 81 of the illustrated pad 43 is spacedtwelve inches from one end 85 of the pad, is centered between the sides87 of the pad and has a width of 28.35 inches and a length of 14.85inches. The width and length of the shoulder support area 81, as well asits shape may vary, but preferably the width is between 25 and 33inches, the length is between 12 and 17 inches and the shape isgenerally that of a mushroom. There is a gap of 6 inches between theshoulder and tail support areas of the pad 43. The tail support area 83of the illustrated pad 43 is elliptical in shape, is centered betweenthe sides of the pad, has a width of 17.55 inches and a length of 12.15inches. This spaces the tail support area 27 inches from the other end89 of the pad. As with the shoulder support area 81, the width andlength of the tail support area 83, as well as its shape, may vary, butpreferably, the width is between 15 and 20 inches, the length is between10 and 17 inches, and the area is generally elliptical or circular inshape.

Although the sizes of the peaks 42 and valleys 44 of the pad 43 may bevaried, the illustrated pad has a uniform distribution of peaks ofsquare cross section. The peaks 42 of the general support area, theshoulder support area 81 and the tail support area 83 all have a peakthickness of 4 inches and a square cross section with a width of 1.35inches. As best seen in FIG. 15, to provide the desired loweredresistance and body contouring features, the valley thicknesses of theshoulder and tail support sections of the pad are less than the valleythicknesses of the general support area of the pad. Specifically, thevalley thickness for both the shoulder support area 81 and the tailsupport area 83 is one half of one inch, while the valley thickness forthe general support area is 3 inches.

Advantageously, the bed pad 43 is formed by means of inserting a block19 of foam lengthwise through a roller having a circumference equal tothe length of the bed pad 43, so that a pair of pads is formed by asingle turn of the roller. Thus, the illustrated pad 43 would be formedwith two rollers each having a circumference of 72 inches. The fingers15 of each roller corresponding to the general support area of the pad43 advantageously extend radially 2.5 inches from the cylindrical coreof the roller and have a square cross section with a width of 0.9inches. This width may vary, but is preferably between 1.25 and 2.0inches. The space between the opposing rollers, 13 and 14, is roughlyone quarter of an inch, with this distance being shortened where therollers are provided with caps. The fingers 15 of the rollercorresponding to the shoulder support area 81 and the tail support area83 are advantageously formed by fingers 15 with an effective fingerheight of 2.6875 inches, resulting from the placing of caps 23 having acombined thickness of 3/16 of an inch onto the end of the fingers 15.The resulting bed pad 43 is 4 inches thick with a valley thickness of0.5 inches which is sufficient to prevent bottoming out in most cases.

In a test comparing a bed pad, generally conforming to thespecifications set forth above, with static water, static air and otherconvoluted foam support pads, the bed pad of the present invention notonly demonstrated pressure relief capabilities, in the scapulae, sacrumand trochanter areas, superior to the other convoluted foam bed padstested, but demonstrated pressure redistribution capabilities in theseareas comparable to the static air and water support pads tested.Specifically, the pads tested are as follows:

    ______________________________________                                                                    Model                                             Designation Manufacturer                                                                      Trademark   No.      Type                                     ______________________________________                                        Foam #1*                                                                              Pre-Foam, Inc.                                                                            HIGHFLOAT   5095020                                                                              foam                                   Water   Lotus                                                                         Healthcare                                                                    Products    LOTUS       HM3666 water                                  Air     Gaymar                                                                        Industries,                                                                   Inc.        SOF•CARE                                                                            SC-402 air                                    Foam #2 Bio Clinic  BIOGARD     669030 foam                                           Company                                                               Foam #3 Span America                                                                  Medical                                                                       Systems,                                                                      Inc.        GEO-MATT    50960-581                                                                            foam                                   Foam #4 Pre-Foam, Inc.                                                                            PREVENT     P141   foam                                   ______________________________________                                         *Foam Pad #1 is a pad made in accordance with the principles of the           present invention.                                                       

A summary of the test results are set forth below in the followingtable:

    ______________________________________                                                Pressure Level                                                        Pad       Scapulae    Sacrum   Trochanter                                     Designation                                                                             (mm Hg)     (mm Hg)  (mm Hg)                                        ______________________________________                                        Foam #1*  24.02       28.28    44.22                                          Water     22.44       25.96    46.74                                          Air       32.36       33.15    40.57                                          Foam #2   29.26       34.40    47.17                                          Foam #3   23.04       31.97    49.73                                          Foam #4   28.04       36.88    45.97                                          ______________________________________                                    

Thus, there is provided a convoluted foam bed pad which is both simpleand inexpensive to manufacture and which provides high pressureredistribution capabilities comparable to static air and water supportpads.

The method and teachings of the present invention can be used tomanufacture pads of a wide variety of shapes and sizes. Specifically,the method of the present invention can be used to manufacture pillowsand wheelchair pads which conform to the shape of the body, therebyincreasing the total surface area of the pad resisting the body weightof the user.

FIGS. 10 and 12 show a pillow 93 having a generally T-shaped head andneck support area 95 and a general support area 97. As with the bed pad43, the pillow 93 is formed by peaks 99 arranged in rows, wherein eachpeak has a flat top, is spaced from any adjacent peak in the same row bya valley 101 and has generally identical peak thicknesses. The tops ofthe peaks are all in substantially the same plane, thereby providing apillow 93 of pleasing appearance which can be used with standard pillowcovers. To increase the pillow's capacity to conform to the head andneck of the user, the average valley thickness of the head and necksupport area 95 is less than the average valley thickness of the generalsupport area 97. Although the dimensions of the pillow 93 can obviouslybe varied widely, depending upon the desired application, theillustrated pillow 93 has a width of 21 inches and a depth of 14 inches,with a uniform peak thickness of 4 inches. The truncated stem 103 of theT-shaped head and neck support area 95 extends toward the center of thepillow 93 from one end 105, is centered between the sides 106 of thepillow and has a width of 4.05 inches. The crossbar 107 of the T-shapedhead and neck support area 95 extends from one side of the pillow to theother, is spaced 4.05 inches from the end of the pillow from which thestem portion extends, and has a depth of 4.05 inches. This spaces thestem portion 5.90 inches from the opposite end 111 of the pillow. Thedesired contouring effect may be obtained from a T-shaped head and necksupport area 95 with an average valley thickness of 1/2 an inch and thegeneral support area 97 with a uniform valley thickness of 3 inches.

FIGS. 11 and 13 show a wheelchair pad 113 having a generally U-shapedbuttock and thigh support area 115 and a general support area 117. Aswith the pillow 93 and bed pad 43, the wheelchair pad 113 is formed bypeaks 119 arranged in rows, wherein each peak has a flat top, is spacedfrom any adjacent peak in the same row by a valley 121 and has generallyidentical peak thickness. The tops of the peaks are also all insubstantially the same plane, thereby providing a wheelchair pad 113 ofpleasing appearance. To increase the wheelchair pad's capacity toconform to the buttocks and thighs of the user, the average valleythickness of the buttock and thigh support area 115 is less than theaverage valley thickness of the general support area 117. Although thedimensions of the wheelchair pad 113 can obviously be varied, dependingupon the size of the chair and the user, the illustrated wheelchair pad113 has a width of 18 inches and a depth of 16 inches, with a uniformpeak thickness of 41/2 inches. The legs 123 of the T-shaped buttock andthigh support area 115 extend toward the opposite end of the wheelchairpad from one end, are spaced 2.295 inches from the sides of thewheelchair pad and have a width of 4.05 inches. An arcuate connectingportion 125 connects the two legs of the U-shaped buttock and thighsupport area 115, is spaced 11/4 inches from the opposite end of thewheelchair pad, and has a width of 4.05 inches. The desired contouringeffect may be obtained from a U-shaped buttock and thigh support area115 with an average valley thickness of 3/4 inches and the generalsupport area 117 with a uniform valley thickness of 31/2 inches.

What is claimed is:
 1. An elongate convoluted foam pad for supporting areclining human body on a bed, comprising:a bottom; a shoulder supportarea for supporting the shoulder portion of a body formed by peaksarranged in rows, wherein each peak has a substantially flat top and isspaced from any adjacent peak in the same row by a valley; a tailsupport area for supporting the tail portion of said body formed bypeaks arranged in rows, wherein each peak has a substantially flat topand is spaced from any adjacent peak in the same row by a valley; and ageneral support area surrounding said shoulder support area and saidtail support area formed by peaks arranged in rows, wherein each peakhas a substantially flat top and is spaced from any adjacent peak in thesame row by a valley, said valleys of said shoulder support area, saidvalleys of said tail support area and said valleys of said generalsupport area each having an average valley thickness, wherein each ofsaid peaks has a substantially uniform peak thickness and wherein saidaverage valley thickness of said valleys in said shoulder support areaand said average valley thickness of said valleys in said tail supportarea are less than said average valley thickness of said valleys in saidgeneral support area.
 2. The pad of claim 1, wherein all of saidsubstantially flat tops are included in a single plane.
 3. The pad ofclaim 2, wherein said pad is formed from a polyurethane foam having adensity of between one and three pounds per cubic foot.
 4. The pad ofclaim 3, wherein said peaks have a peak thickness between one and fiveinches.
 5. The pad of claim 4, wherein some of said peaks have cornersand some of said corners are connected to other of said corners of otherpeaks by webbing.
 6. The pad of claim 5, wherein at least some of saidcorners are not connected by webbing, thereby providing a locale ofdecreased resistance to pressure.
 7. A convoluted foam pad forsupporting a human body on a bed, comprising:a bottom; a general supportarea; a shoulder support area; and a tail support area, each of saidareas comprising adjacent rows of peaks having substantially flat topsand generally rectangular cross sections which form corners, said peaksin each row being separated by valleys and said peaks in adjacent rowsbeing staggered, said valleys of said shoulder support area, saidvalleys of said tail support area and said valleys of said generalsupport area each having an average valley thickness, said averagevalley thickness of said valleys in said general support area beinggreater than said average valley thickness of said valleys in saidshoulder support area and greater than said average valley thickness ofsaid valleys in said tail support area, said peaks and said valleysforming a checkerboard pattern wherein at least some of said corners ofsaid peaks in adjacent rows are connected by webbing.
 8. The pad ofclaim 7, wherein at least some of said corners of said peaks in adjacentrows are not connected by webbing, thereby decreasing the resistance ofthe locale including the nonconnected corners to pressure.
 9. Aconvoluted foam pillow for supporting the head and neck of a body,comprising:a bottom; a general support area formed by peaks arranged inrows, wherein each peak has a substantially flat top and is spaced fromany adjacent peak in the same row by a valley; and a generally T-shapedhead and neck support area formed by peaks arranged in rows, whereineach peak has a substantially flat top and is spaced from any adjacentpeak in the same row by a valley, wherein each of said peaks has asubstantially uniform peak thickness said valleys of said generalsupport area and said valleys of said head and neck support area eachhaving an average valley thickness, wherein said average valleythickness of said valleys in said head and neck support area is lessthan said average valley thickness of said valleys in said generalsupport area, thereby forming an area of greater capacity to conform tothe shape of said head and said neck of said body.
 10. The pillow ofclaim 9, wherein all of said substantially flat tops are included in asingle plane.
 11. The pillow of claim 10, wherein said pillow is formedfrom a polyurethane foam having a density of between one and threepounds per cubic foot.
 12. The pillow of claim 11, wherein said peakshave a peak thickness between one and five inches.
 13. The pad of claim12, wherein said peaks form corners and some of said corners of saidpeaks are connected to said corners of other of said peaks by webbing.14. The pad of claim 13, wherein at least some of the corners of saidpeaks are not connected by webbing, thereby providing a locale ofdecreased resistance to pressure.
 15. A convoluted foam wheelchair padfor supporting the thigh and buttocks of a body on a wheelchair,comprising:a bottom; a general support area formed by peaks arranged inrows, wherein each peak has a substantially flat top and is spaced fromany adjacent peak in the same row by a valley; and a generally U-shapedthigh and buttock support area formed by peaks arranged in rows, whereineach peak has a substantially flat top and is spaced from any adjacentpeak in the same row by a valley, wherein each of said peaks has asubstantially uniform peak thickness, said valleys of said generalsupport area and said valleys of said thigh and buttock support areaeach having an average valley thickness, wherein said average valleythickness of said valleys in said thigh and buttock support area is lessthan said average valley thickness of said valleys in said generalsupport area, thereby forming an area of greater capacity to conform tothe shape of said thighs and buttocks of said body.
 16. The pad of claim15, wherein all of said substantially flat tops are included in a singleplane.
 17. The pad of claim 16, wherein said pad is formed from apolyurethane foam having a density of between one and three pounds percubic foot.
 18. The pad of claim 17, wherein said peaks have a peakthickness between one and five inches.
 19. The pad of claim 18, whereinsaid peaks form corners and some of said corners of said peaks areconnected to the corners of other peaks by webbing.
 20. The pad of claim19, wherein at least some of said corners are not connected by webbingto other of said peaks, thereby providing a locale of decreasedresistance to pressure.